I use diffusion (RPG Modffractal)between the speakers and absorption/diffusion (RPG ARC BAD Panels) behind the speakers. On the back wall I have absorption/diffusion. In the corners I use absorption (RealTraps Mondo Traps) and on the front and back wall/ceiling corner I use absorption/diffusion.
I had the room measured to place the panels. it sounds great!
I had the room measured to place the panels. it sounds great!